Democratic presidential candidates hammer President Donald Trump over his trade war with China.

The rhetoric shows a Democratic field more comfortable with criticizing the president on trade as concerns grow about the conflict dragging on global growth.

Pete Buttigieg pointed out that Trump had previously argued the small-city official would not be able to negotiate with Chinese President Xi Jinping. "I'd like to see him make a deal with Xi Jinping," Buttigieg cracked.

Democratic presidential hopefuls hammered President Donald Trump over his trade war with China in Thursday's debate as fears grow about the conflict shaking the global economy.

The 10 candidates on stage in Houston portrayed an impulsive president with little concrete plan to force Beijing to change what Trump calls unfair trade practices.

Both entrepreneur Andrew Yang and former Housing and Urban Development Secretary Julian Castro called the White House's decisions "haphazard." Sens. Bernie Sanders, I-Vt., and Kamala Harris, D-Calif., called out the president's penchant for announcing trade policy through tweet.

The pile on shows a field more comfortable with picking apart Trump's economic conflict with the world's second largest economy than they were even a few months ago. As companies and consumers show more uneasiness about escalating rounds of tariffs on American and Chinese goods, Democrats came prepared to score points over the president's trade policy.

South Bend, Indiana, Mayor Pete Buttigieg pointed out that Trump had previously argued the small-city official would not be able to negotiate with Chinese President Xi Jinping. "I'd like to see him make a deal with Xi Jinping," Buttigieg cracked Thursday, referencing Trump's months long effort to strike a trade agreement with China.

Democratic presidential hopeful Mayor of South Bend, Indiana, Pete Buttigieg speaks during the third Democratic primary debate of the 2020 presidential campaign season hosted by ABC News in partnership with Univision at Texas Southern University in Houston, Texas on September 12, 2019.

In a statement responding to the Democrats on Friday morning, Trump campaign spokeswoman Kayleigh McEnany said the president "has repeatedly advocated for the American worker on the world stage by taking on unfair trade practices across the world." She argued that, "if Democrats truly cared about trade, they would partner with President Trump" and pass his replacement for the North American Free Trade Agreement.

The candidates have good reason to highlight the trade war's effect on farmers, in particular. Iowa, where China's retaliatory tariffs on crops have done damage, hosts the first-in-the-nation caucus in February.

While most of the 10 candidates on stage Thursday eviscerated Trump's policies, they created distance from one another on trade. Both Yang and Buttigieg said they would not immediately get rid of the president's duties on Chinese goods.

Sanders and Sen. Elizabeth Warren, D-Mass. — whose trade views both overlap with Trump's — highlighted a U.S. trade policy that they said has harmed workers for years.

Democratic presidential hopeful Vermont Senator Bernie Sanders speaks during the third Democratic primary debate of the 2020 presidential campaign season hosted by ABC News in partnership with Univision at Texas Southern University in Houston, Texas on September 12, 2019.

Robyn Beck | AFP | Getty Images

"Our trade policy in America has been broken for decades and it has been broken because it works for giant multinational corporations and not for much of anyone else," Warren said.

Sanders called American trade policy "disastrous." He also drew a distinction between himself and the primary's frontrunner, former Vice President Joe Biden, on trade policy. The senator said he "strongly disagreed" with Biden, highlighting his opposition to the North American Free Trade Agreement, which Biden supported.

Biden, like his rivals, said both labor groups and environmentalists need a larger role in trade policy. He also said the U.S. and China need to determine the world's trading relationships or "China's going to make the rules of the road."